In the use of conventional fishing line rudders, it is the usual practice to affix--inconveniently and not always with effective results--depth control weights to the line or leader, while the swivel--as coupled between the rudder and leader--is wholly exposed and hence subject to tangling as well as wear and tear on its working parts due to the intrusion of foreign substances such as sand, silt, and other abrasive materials. The present invention was conceived in a successful effort to avoid such inconvenience and overcome such problem.